1.Field of the Invention
The present invention relates to a process for producing a thiophene derivative. More particularly, the present invention relates to a process for producing a thiophene derivative useful for an intermediate of biotin (vitamin H).
2.Description of the Related Art
There has been known heretofore a process for producing a thiophene as expressed by the general formula (2): ##STR1## as disclosed in Japanese Patent KOKAI (Laid-open) No. Sho 61-151194. This process uses palladium oxide as a palladium catalyst.
However, the above process has a disadvantage of requiring a great amount of the expensive palladium catalyst for the production of the compounds expressed by the general formula (2) owing to a low catalytic activity in the process.